Do we need to know the pKa of the side chains of amino acids?

[LSD-25]

I'm wondering because some people were talking about this on the new mcat.

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[sazerac]

I would think knowing acid is 2, amino is 9, and histidine is 6.5 is fair game. Everything else could be inferred.

Take serine for example. What do you suppose is the pKa of that H in the side chain? Let's say your answer choices are 0, 2, 4, or 6.

 

[NextStepTutor_1]

I would say you can get away without knowing the exact side chain pKa values for the amino acids. If you know the categories well (and if you have the side chains memorized), then you can use some intuition in this context (but only some). I have yet to run into a practice question where it was required to know the side chain pKas to answer the question and they weren't provided in the passage.
With that said, I have heard that the April test tested more on amino acids than people thought, so memorizing the side chains would be a good idea and as @sazerac notes knowing some unique pKas for side chains certainly couldn't hurt.